From: Joerg Roedel <[email protected]> Not doing so is a bug and might trigger a BUG_ON in handle_mm_fault(). So add the proper permission checks before calling into mm code.
Signed-off-by: Joerg Roedel <[email protected]> --- drivers/iommu/intel-svm.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index c69e3f9..4ebf097 100644 --- a/drivers/iommu/intel-svm.c +++ b/drivers/iommu/intel-svm.c @@ -484,6 +484,14 @@ struct page_req_dsc { }; #define PRQ_RING_MASK ((0x1000 << PRQ_ORDER) - 0x10) + +static bool access_error(struct vm_area_struct *vma, struct page_req_dsc *req) +{ + return !((req->rd_req && (vma->vm_flags & VM_READ)) || + (req->wr_req && (vma->vm_flags & VM_WRITE)) || + (req->exe_req && (vma->vm_flags & VM_EXEC))); +} + static irqreturn_t prq_event_thread(int irq, void *d) { struct intel_iommu *iommu = d; @@ -539,6 +547,9 @@ static irqreturn_t prq_event_thread(int irq, void *d) if (!vma || address < vma->vm_start) goto invalid; + if (access_error(vma, req)) + goto invalid; + ret = handle_mm_fault(svm->mm, vma, address, req->wr_req ? FAULT_FLAG_WRITE : 0); if (ret & VM_FAULT_ERROR) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
